Control system for water treatment apparatus



Aug. 14, 1962 R. A. WHITLOCK ETAL CONTROL SYSTEM FOR WATER TREATMENT APPARATUS 4 Sheets-Sheet 1 Filed Aug. 8, 1958 *1 E 2 I R 3 w Aug. 14, 1962 R. A. WHITLOCK ET AL 3,049,237

CONTROL SYSTEM FOR WATER TREATMENT APPARATUS 4 Sheets-Sheet 2 Filed Aug. 8, 1958 vb kn n 1962 R. A. WHITLOCK ET AL 3,049,237

CONTROL SYSTEM FOR WATER TREATMENT APPARATUS Filed Aug. .8, 1958 4 Sheets-Sheet 3 'Aug- 1962 R. A. WHITLOCK ET AL 3,049,237

CONTROL SYSTEM FOR WATER TREATMENT APPARATUS 4 Sheets-Sheet 4 Filed Aug. 8, 1958 tats 3,049,237 Patented Aug. 14, 1962 Filed Aug. 8, 1958, Ser. No. 754,972 21 Claims. (Cl. 210-136) This invention relates to a control system for a water treatment apparatus.

An important object of this invention is to provide a simple and economical control system for a water treatment apparatus, which control system is arranged to effect flow in one direction through the treatment tank to drain for backwashing of the bed of exchange material and flow in the other direction to the treatment tank to drain during regeneration and rinsing of the bed of exchange material.

A more particular object of this invention is to provide a control system for a water treatment apparatus including a fluid actuated three-way valve connected to the treatment tank for reversibly controlling the flow of liquid therethrough together with a pair of drain valves operative when a first of the drain valves is open to actuate the flow reversing valve and pass fluid in one direction through the treatment tank to drain and operative when the other drain valve is open to pass regenerant and rinse water in the other direction to the treatment tank to drain.

Another object of this invention is to provide a control system in accordance with the foregoing object and which has an ejector for delivering regenerant to the treatment tank and a novel arrangement for preventing flow through the ejector during the service and backwash phases of the regeneration cycle.

A further object of this invention is to provide a control system for a water treatment apparatus including a flow reversing three-way valve having first and second outlets connected to the treatment tank and operative to pass water from the first outlet in one direction through the treatment tank to service; a first drain valve operative upon opening to actuate the three-way valve to close the fi st outlet and pass water from the second outlet in the reverse direction through the tank to drain during backwashing; a regenerant injector; a second drain valve operative upon opening to retain said three-way valve in a position closing said first outlet to pass regenerant from said ejector in said one direction through the treatment tank to drain, and an auxiliary valve operative when the second drain valve is opened to block the flow of water from said second outlet to the treatment tank.

Still another object of this invention is to provide a control system for a water treatment apparatus which is completely automatic in operation and which is reliable and eflicient in use.

These, together with various ancillary objects and advantages of this invention will be more readily appreciated as the same becomes better understood by reference to the following detailed description when taken in connection with the accompanying drawings wherein:

FIGURE 1 is a diagrammatic view of the control system of the present invention with the control valve shown in section and illustrating the same in the service position thereof;

FIG. 2 is a fragmentary diagrammatic view of the control system showing the valves in the backwash position and illustrating a slightly modified arrangement for regulating the backwash rate of flow;

FIG. 3 is a fra mentary diagrammatic view of the control system of FIG. 2 and showing the valves in the regeneration and rinse positions;

FIG. 4 is a fragmentary sectional view through a flow controller for regulating the backwash rate in the embodiments of FIGS. 2 and 3;

FIG. 5 is a diagrammatic view of a modified form of control system with the control valve shown in section and illustrating the same in the service position;

FIG. 6 is a diagrammatic view of the control system of FIG. 5, with the valve shown in section and in the brining and rinse positions thereof;

FIG. 7 is a longitudinal sectional view through a further modified form of valve; and

FIG. 8 is a longitudinal sectional view taken on the plane 8-8 of H6. 7 and illustrating the valve member in a moved position.

The control system of the present invention is arranged to regulate the flows of fluid to and from the treatment tank 10 during the service run and during the backwash, brining and rinse phases of the regeneration cycle. The present control system is arranged to eflect the flow of liquid downwardly through the treatment tank to service, during the service run; upwardly through the treatment tank to drain during the backwash phase of the regeneration cycle; and downwardly through the treatment tank to drain during the regeneration and rinse phases of the regeneration cycle.

In general, the control system includes a fluid actuated three-way valve 11, a first drain valve 12 operative upon opening to actuate the valve 11 and effect reversal of flow through the treatment tank 10; a second drain valve 13 operative when open to pass fluid downwardly through the treatment tank to drain; an ejector 14 for introducing a measured quantity of regenerant into the top of the treatment tank during the regeneration of the bed of exchange material; a regenerant tank 15 having a valve mechanism 16 therein for controlling the flow of regen-. erant to the ejector 14 and auxiliary valve mechanism 17 for regulating the flow of fluid to and from the bottom of the treatment tank. In the embodiment illustrated in FIGS. 1-4, the drain valves 12 and 13 and the auxiliary valve 17 are solenoid operated and a timer 18 is provided for effecting operation of the respective valves in proper timed sequence.

Referring more specifically to FIGS. 1-4, the flow reversing valve 11 includes a casing 21 defining an inlet chamber 22 having an inlet passage 23 (see FIGS. 2 and 3) and spaced outlet ports 24 and 25. In this embodiment, the outlet ports 24 and 25 are formed in fittings 26 and 27 which are inserted into the casing and define opposed valve seats 28 and 29. A valve member 31 is disposed in the inlet chamber and has upper and lower valve faces 32 and 33 arranged to respectively engage the valve seats 28 and 29. In the service run, the valve member 31 is positioned as shown in FIG. 1 seated against the seat 29 to block flow through the lower port 25 and permit flow from the inlet passage 23 through the upper outlet port 24.

The valve 11 also includes upper and lower flow chambers 36 and 37 formed by casing extensions 38 and 39. In the specific form illustrated, the casing extensions are formed integrally with the casing 21, it being understood that the casing extensions may be formed separate therefrom. The upper flow chamber 36 is connected through a top outlet passage 41 to a conduit 42 leading to the top of the treatment tank 10. The lower flow chamber 37 is connected through a conduit 43 to the lower end of the treatment tank and the auxiliary valve 17 is arranged to control the flow of liquid between the conduit 43 and the lower flow chamber 37. In order to provide a more compact unit, the auxiliary valve 17 is mounted in' the lower casing extension 39 and includes a movable valvemember 45 which is yieldably urged to a position blocking flow through the port 46, as by a valve spring 47.

In the disclosed arrangement, the auxiliary valve is arranged to be operated by the solenoid 48 which, when energized, retracts the movable member 45 away from the port 46 to permit flow of fluid therethrough.

The service outlet passage 51 is advantageously formed in the casing extension 39 to communicate with the lower; flow passage 37. With this arrangement, a flow of raw water to service is provided during regeneration of the bed of exchange material. A by-pass 52 is provided around the auxiliary valve 17 to permit flow of treated water from the tank and conduit 43 to the service outlet 51 and a check valve 53, herein shown in the form of a ball-type valve is provided for preventing reverse flow through the passage 52.

An upper drain passage 55 is formed in the upper casing extension 38 and communicates with the chamber 36 therein. A drain conduit 56 communicates with the drain passage and the aforementioned drain valve 12 is provided for controlling the flow of liquid through the drain passage. The valve 12 is normally closed and is operated by a solenoid 57 to its open position. As shown herein, an enlarged head 61 is attached to the upper end of the stem 62 connected to the valve member 31. The periphery of the head extends into closely spaced adjacency to an annular rib 63 formed in the casing extension between the top outlet passage 41 and the drain passage 55 to define a restricted flow passage therebetween. When the drain valve 12 is opened, the pressure on the top of the head 61 is reduced whereby fluid under substantially inlet pressure at the underside of the head efiects raising of the latter until the valve member 31 seats against the downwardly facing seat 28. This blocks flow through port 24 and opens the lower port so as to effect flow therethrough to the bottom of the treatment tank for backwashing the bed of exchange material.

In the embodiment illustrated in FIG. 1, the backwash rate of flow is regulated by means of a flow regulator 65 interposed between the port 46 and the conduit 43. This flow regulator may be of any conventional construction and as illustrated herein includes an annular port member 66 having a V-shaped end face 67 and a resilient valve member 68 cooperates with the end face to regulate the flow therethrough in response to the pressure on opposite sides of the resilient valve member 68. This arrangement is of conventional construction and is so designed as to provide a preselected substantially constant rate of flow therethrough substantially independent of variations of pressure.

In accordance with the present invention, provision 1s made for effecting downflow of the regenerant and rinse water through the treatment tank 10. This is effected by providing a second drain passage 71 in communication with the lower conduit 43 for selectively passing fluid from the lower conduit through the second drain conduit 72 and drain valve 13 to drain. At the end of the backwash phase of the regeneration cycle, the upper drain valve 12 is closed and the lower drain valve 13 is opened. Opening of the lower drain valve communicates the upper flow chamber 36 to drain through the conduit 42, tank 10, conduit 43 and drain passage 71 so as to maintain the upper flow chamber at a relatively low pressure. Since the liquid in the inlet chamber 22 is at substantially line pressure, there is -a pressure unbalance acting on the valve member 31 which maintains the same in its raised position, even when the upper drain valve 12 is-closed. Simultaneously, the solenoid 48 of the auxiliary valve 17 is deenergized to permit closing of the auxiliary valve to prevent the passage of raw water through the port 46 to the lower drain conduit 72.

An ejector 14 is provided for feeding regenerant to the upper conduit 42, when the lower drain valve 13 is open. The ejector 14, as is conventional, includes a raw water inlet chamber 75, a regenerant inlet chamber 86, and an outlet chamber 77. The nozzle 78 is interposed between the hard water inlet chamber and the rethe pressure in the inlet chamber.

generant chamber and a throat 79 is interposed between the regenerant chamber and the outlet chamber 77. When the pressure at the outlet chamber 77 is substantially less than the pressure at the ejector inlet chamber 75, water will flow through the nozzle 78 and into the throat 79 and produce a low pressure condition in the regenerant inlet chamber 76. A regenerant inlet conduit 81 communicates at one end with the chamber 76 and at the other end with a regenerant tank 15 through the regenerant control valve 16. Water at inlet pressure is supplied to the inlet chamber 75 of the ejector through a conduit 82 which communicates at one end with the inlet chamber 22 and at the other end with the ejector inlet chamber 75. When the drain valve 13 is opened, the pressure in the upper chamber 36 is reduced substantially below line pressure so that raw water flows through the ejector 14 to draw regenerant from the tank 15 and pass the same to the conduit 42 and top of the treatment tank 10. The effluent from the bottom of the treatment tank flows outwardly through the lower drain valve 13 to drain.

The regenerant control valve 16 may be of any conventional type such as the float operated valve disclosed in the patent to Whitlock No. 2,716,422, and which is arranged to cut ofi the flow of regenerant to the ejector when a preselected quantity of regenerant has been drawn from the regenerant tank 15, and to also shut off the flow of water to the regenerant tank, when the liquid level in the regenerant tank reaches a preselected upper level. With this arrangement, the flow of regenerant to the ejector 14 will be interrupted after a preselected quantity of regenerant has been supplied to the treatment tank 10. The raw water from the inlet passing through the ejector will thereafter be eifective to slowly rinse the bed of exchange material in the tank, the

eflluent from the treatment tank 10 passing through the conduit 43, drain passage 71 and conduit 72 to drain.

tor 14 will therefore build up the pressure in the tank 10 and in the upper flow chamber 36 until the pressure in the upper flow chamber is substantially equal to The valve member 31 may then move downwardly under its own weight to a position on the seat 29 blocking flow through the lower port 25.

I solenoid operated, as by solenoids 57 and 74 respectively and the timer 18 is arranged to effect operation of the solenoids 57, 48 and 74 in proper timed sequence. The timer 18 may be of any conventional construction arranged to energize a first circuit 91 for a preselected time interval corresponding to the backwash phase of the regeneration cycle and to thereafter energize a second circuit 92 for a time interval corresponding to the duration of the regeneration and rinse phases of the regeneration cycle. As shown in FIG. 1, the circuit 91 is connected through conductors 93 and 94 to the solenoids 57 and 48 to simultaneously open the upper drain valve 12 and open the auxiliary valve 17, during the backwash phase of the regeneration cycle. The circuit 92 is connected to the solenoid 74 so as to open the.

lower drain valve 13 when the upper drain valve and the auxiliary valve 17 are closed. I

Since the flow regulator in FIG. 1 is essentially a variable flow impedance, it produces a pressure drop thereacross. Consequently, the pressure at the outlet side of the flow regulator is less than the pressure in the inlet chamber 22. Since the pressure at the outlet side of the regulator 65 is transmitted through conduits 43, tank 10 and conduit 42 to the upper flow chamber 36, it is apparent that the pressure in the last-mentioned chamber isalso less than inlet pressure. In order to prevent appreciable flow of regenerant to drain through the top drain valve 12, when the latter is opened, the

ejector 14 in the embodiment of FIG. 1 is made relatively ineflicient so as to prevent the drawing of brine 81 until the pressure differential between the ejector inlet chamber 75 and the ejector outlet chamber 77 reaches a preselected value. This can be achieved by enlarging the size of the throat 79 sufiicient to prevent the formation of a vacuum in the regenerant chamber 76 under the pressure conditions in the top flow chamber 36 which exist during backwash. The outlet 13a of the lower drain valve 13 is arranged to discharge at a level appreciably below the level of the outlet 12a for the upper drain valve so as to produce a syphon effect when the lower drain valve 13 is opened. This reduces the pressure in the upper flow chamber 36, when the lower drain valve 13 is opened, to a value below that which exists when the upper drain valve is open. The ejector 14- is so designed as to feed regenerant to the conduit 42, under the pressure condition existing at the outlet thereof, when the lower drain valve is open.

In the embodiment of FIGS. 2 and 3, the flow restrictor 95 is connected in the drain line 56 leading to the upper drain valve 12. The flow restrictor 95 may be Of any conventional construction such as shown in FIG. 4 and includes a body having a stepped passage 96 therein and a resilient ported disk 97 disposed in the passage. With this arrangement, the disk 97 is deflected to a somewhat concavo-convex shape by the pressure unbalance on opposite sides thereof and the edges of the disk around the central opening 98 therein move inwardly to constrict the opening in proportion to the pressure unbalance thereon. This arrangement also provides a substantially constant flow which is independent of pressure variations.

By restricting the backwash rate of flow in the upper drain conduit 56, a relatively high pressure is maintained during backwash throughout the entire system including the upper flow chamber 36. This pressure in the flow chamber is effective to prevent sufiicient flow through the ejector 14 to cause feeding of regenerant during backwash. However, when the second drain valve 13 is thereafter opened, the pressure in the tank in the upper flow passage 36 is reduced to a low level so that the ejector is operative to feed regenerant.

From the foregoing it is thought that the operation of the control system of FIGS. 1-4 will be readily understood. During the service run, the valve member 31 is in the position shown in FIG. 1 and raw water flows from the inlet passage 23 through the top conduit 42 and downwardly through the tank 10. The treated water from the tank flows through conduit 43, past check valve 53 to the service outlet 51. In order to effect backwashing, the upper drain valve 12 is opened and the auxiliary valve 17 simultaneously opened. Opening of the drain valve 12 effects raising of the valve member 31 to a position blocking flow through the port 24 and opening the port 25. Raw water then flows through the port 25, through chamber 37 and port 46 to the conduit 43. The water flows upwardly through the treatment tank 10 to backwash the same and the effluent flows outwardly through conduit 42, upper chamber 36 and outwardly through the drain passage 55 to drain.

Regeneration is effected by closing the upper drain valve 12 and the auxiliary valve 17 and simultaneously opening the lower drain valve 13. When the lower drain valve is opened, it passes the water fromv the treatment tank 16 downwardly through conduit 43 to drain. This reduces the pressure in the upper flow passage 36 so that there is a pressure unbalance on the valve member 31 which retains it in its raised position even when the upper drain valve 12 is closed. Reducing the pressure in the upper flow passage 36 also causes flow through the ejector 14 which draws regenerant from the regenerant tank md feeds the same to the upper conduit 42. The spent regenerant after passing through the treatment tank flows through conduit 43 to the lower drain passage As will be noted, during service the flow occurs through the three-way valve 11 and check valve 52. Since fluid flows through the valves 12, 13 and 17 only during regeneration of the bed of exchange material, and as these flows are relatively small as compared to service flow, the valves 12, 13 and 17 can be relatively small and economical valves.

A modified form of control apparatus is illustrated in FIGS. 5 and 6 and employs a fluid pressure operated auxiliary valve 17a. As in the preceding embodiment, the valve 11a includes a casing 101 defining an inlet chamber 102 having an inlet passage 103 and spaced outlet ports 104 and 105. A ferrule 106 is pressed into the lower port and defines a lower valve seat 107. The upper port 104 is preferably in the form of a smooth cylindrical surface.

The valve member 109 is disposed in the inlet chamber 102 and has a gasket 110 on the underside thereof arranged to engage the lower seat 107 to block flow through the port 105, when the valve member is in its lowered position. A resilient cup washer 111 is mounted on the upper side of the valve member 109 and a fitting 112 overlies the upper face of the cup washer to prevent axial distention of the latter when the valve member is in its raised position. When the valve member is raised, the cup washer engages the cylindrical surface of the upper port 104 and the pressure at the underside thereof tends to force the skirt portion outwardly into sealing engagement with the port. A stop means, to be described hereinafter is provided for limiting upward movement of the valve member 109.

The valve 11a also includes upper and lower flow chambers 114 and 115 formed in casing extensions 116 and 117. Although the casing extensions are herein shown formed integrally with the valve casing 101, it is .apparent that the casing extensions can be formed separate therefrom and connected thereto by pipes or other fittings. An outlet passage 118 communicates with the upper flow chamber 114 and is arranged for connection through a conduit 119 to the upper end of a treatment tank 10a, the lower flow chamber 115 being connected through a conduit 121 to the other end of the treatment tank. A service outlet 122 communicates with the lower chamber 115 for dehvering treated water to service during the service run, and, as in previous embodiment, the auxiliary valve 17a is arranged to control the flow of liquid between the lower chamber 115 and the outlet conduit 121.

A partition 125 extends across the lower chamber 115 and has a port 126 therein. The port 126 is normally open so that during the service run, raw water flows from the inlet chamber 102 through the upper chamber 114, conduit 119 to the treatment tank 10a and treated water flows from the conduit 121 through the port 126 and through chamber 115 to the service outlet 122. A valve member 127 is provided for controlling the flow of liquid through the port 126 and is arranged to close the latter during the regeneration and rinse phases of the regeneration cycle. The valve member 127 shown herein includes a cup washer 128, the skirt portion of which is arranged to engage the walls of the port 126 and form a seal thereacross when the valve member is moved to the position shown in FIG. 6. A fitting 129 overlies the face of the cup washer to prevent axial distentionthereof.

In order to provide a more compact arrangement, the axis of the port 126 is preferably arranged to extend transverse to the axis of the casing 101. A fluid operator chamber 131 is formed at one side of the casing and in communication with the lower chamber 115 at the side of the partition 125 remote from the service outlet 122. A fitting 132 is threaded into the member 131 and defines a cylinder 133 which loosely and slidably receives a valve operator head 134. "In the embodiment illustrated, the periphery of the head 134 is sealed to the cylinder 133 by an O-ring 135 and a port 136 is provided in the operator head to permit -a preselected flow of fluid thereby. It is apparent that the fit between the head 134 and the cylinder 133 could be made sufficiently loose to permit the desired rate of flow of fluid thereby, in which event the port 136 could be eliminated.

The head 134 is connected to the valve member 127 by means of a stem 137 and, during the service run, the head and valve member are urged to a position opening the port 126 by the flow of treated Water through port 1 26 to the service passage 122. The auxiliary valve member will normally remain in its open position during backwash. However, at high backwash rates, the impinging of the backwash stream on the valve member 127 is sometimes suflicien-t to move the auxiliary valve to its closed position. To prevent this, a spring 138 is provided for yieldably urging the valve member to its open position. A drain conduit 139 communicates with the fluid operator chamber and cylinder 133 and the drain valve 13a controls the flow through the drain conduit 139. The drain valve 13a is normally closed so that the pressures on opposite sides of the head 134 are normally equalized through the port 136 in the head whereby the spring is eflfective to move the valve member to its open position. When the drain valve 13a is opened, the fluid pressure unbalance on the head is efiective to overcome the spring and move the valve member 127 to a position closing the port 126. The siZe of the port 136 is made sufliciently small to produce an appreciable pressure drop on opposite sides of the head 134, when the drain valve 13a is opened, sutficient to move the valve 127 against the bias of spring 138 to a position blocking flow through the port 126. When the valve member 127 closes port 126, the valve member is itself subjected to a pressure unbalance which tends to hold the same in its closed position as long as the drain valve 13a is open. Thus, when the auxiliary valve is in the position shown in FIG. 6, the right hand end is subjected to substantially full inlet pressure while the left hand end is subjected to relatively low pressure due to the passage of fluid to drain through valve 13a. I

An upper drain passage 141 communicates with the upper chamber 114 and is connected through a drain conduit 142 to the upper drain valve 1 2a which controls flow therethrough to drain. valve member through a stem 145, which head has the periphery thereof disposed closely adjacent an inwardly extending rib 146 in the upper chamber 114 so that, when the. upper drain valve 12 is opened, the fluid pressure unbalance on the head 144 is effective to raise the valve member 109 to the position shown in FIG. 6. The head 144 engages the cap 147 on the upper end of the valve oasing, to limit upward movement of the valve member 109. This reverses the flow of fluid through the treatment tank 10, the liquid flowing from the inlet chamber 102 through the lower chamber 115, port 126 and conduit 121 to the bottom of the treatment tank, the efliuent from the top of the treatment tank flowing through conduit 119 and chamber 114 to drain through the conduit 142. As is apparent, the pressure at the inlet chamber 102 will be greater than the pressure in the upper chamber 114, under these conditions, so that there is a fluid pressure unbalance on the valve member 109 which not only aids in retaining the same in its raised position but also presses the cup washer .111 outwardly into snug scaling engagement with the upper passage'104.

At the completion of the backwash phase of the regener-ation cycle, the lower drain valve 13a is opened and the upper drain valve 12a is closed. Opening of the lower A head 144 is attached to the drain valve moves the auxiliary valve member 127 to a position blocking flow through the port'126 so as to shut ofi flow from the inlet chamber 102 to the bottom of the treatment tank. Liquid then flows from the upper chamber 114 and conduit 119 to the top of the treatment tank 10a, and from the bottom of the treatment tank through conduit 121, port 136 in the head 134 to the lower drain line 139. In this manner, the upper chamber 114 is maintained at a reduced pressure below the pressure in the inlet chamber 102 so that the pressure unbalance on the valve member 109 is efiective to maintain the same in its raised position shown in FIG. 6.

Regenerant is supplied to the upper chamber 114 for passage through the treatment tank to drain through the lower drain valve 1311. For this purpose, a regenerant feed passage 151 is connected so as to discharge into the upper chamber 114. As shown herein, the conduit 151 discharges into the chamber 114 above the rib 146, it being apparent that the conduit could communicate with the chamber 114 below the rib 146 or, alternatively, with the conduit 119 leading to the top of the treatment tank. An ejector 14a is provided in the conduit 151 and, as in the preceding embodiment, includes an inlet chamber a, a regenerant inlet chamber 76a and an outlet chamber 77a. An ejector nozzle 78a is positioned between the raw water inlet chamber and the regenerant inlet chamber and a throat 79a is provided between the regenerant inlet chamber and the outlet chamber. When water flows through the nozzle 78:: and into the throat 79a, a reduced pressure is formed in the inlet chamber 76a to draw regenerant thereinto from the afo-redescribed treatment tank 15, under the control of the regenerant valve 16.

Raw water is supplied ot the inlet chamber 75a to flow through the ejector, when the pressure conditions at a the outlet end thereof are sufficiently low. Advantageously, the inlet of the conduit 151 is communicated with a the lower flow chamber through a passage 155 therein. In order to prevent the flow of raw water backwards through the ejector 14a and to the service outlet 122, during the service run, a second valve face. 156 is provided on the valve member 127 and arranged to cooperate With a seat 158 formed around the passage 155 so as to block flow therethrough when the valve member 127 is in a position opening the port 126. During the service run, and also during the backwash phase of the regeneration cycle, the valve member 127 is in a position to close the passage 155 and prevent flow through the ejector 14a. During the regeneration and rinse phases of the regeneration cycle, the valve member 127 is moved to a position blocking flow through the port 126 and opening the passage 155 so that fluid may flow through the ejector to the top of the treatment tank. As previously described, after a preselected quantity of regenerant has been introduced, as determined by the regenerant control valve 16, the flow of regenerant to the ejector is interrupted so that continued flow of raw Water through the ejector serves to rinse the bed of exchange material in the tank. Necessarily, therestriction of the port 136 in the auxiliary valve operator :head 134 is made less than the flow restriction of the ejector 14a so as to maintain the reduced pressure condition in the upper chamber 114.

As in the preceding embodiment, the drain valves 12a and 13a are solenoid operated, as by solenoids 161 and 162 and a timer 163 is provided for sequentially operating the solenoids. The timer is arranged to sequentially energize the solenoid 161, through a first circuit 164 to open the drain valve 12 and to thereafter energize the solenoid 162 through a second circuit 165 at or slightly before the first circuit 164 is deenergized, to efiect opening of the lower drain valve 13.

The operation of the control valve of FIGS. 5 and 6 is the same as that of FIGS. 1-4 except that the auxiliary valve -17 is normally open and is fluid pressure operated to its closed position in response to opening of the lower drain valve 13. In addition, the control valve of FIGS. and 6 is arranged to valve the flow of liquid through the regenerant feed conduit 151.

The embodiment of FIGS. 7 and 8 also includes a three-way valve 11b, a first drain valve 12b operated upon opening to actuate the valve 11b and efiect reversal of flow through the treatment tank b; a second drain valve 13b operative when open to pass fluid downwardly through the treatment tank to drain; an ejector 14b for introducing a measured quantity of regenerant into the top of the treatment tank during the regeneration of the bed of exchange material; a regenerant tank 15b having a valve mechanism 16b therein for controlling the flow of regenerant to the ejector and an auxiliary valve mechanism 17b for regulating the flow of fluid to and from the bottom of the treatment tank.

It is a feature of the embodiment of FIGS. 7 and 8 that the valve body 201 is so constructed and arranged that each of the first and second drain valves 12b and 13b, the ejector 14b and the auxiliary valve 17b as well as the interconnecting passages are all formed in and attached directly to the valve body. More particularly, the valve body 201 includes an inlet chamber 202, a top chamber 203 and a bottom chamber 204 interconnected by ports 205 and 206 respectively. A valve member 207 herein shown of the cup washer type previously dmcribed in connection with the embodiments of FIGS. '5 and 6, is provided in the inlet chamber 202 and is movable from the position shown in FIG. 7 blocking flow through port 206 to a raised position as shown in FIG. 8 blocking flow through the port 205. A valve operating head 203 is preferably attached to the upper end of the valve stem 209 for aiding in raising the valve member when the first drain valve 12b is opened. The top chamber 203 has a port 211 formed therein which is connected through a conduit 212 to the top of the treatment tank 10b and the lower chamber 204 is connected through a conduit 213 to the bottom of the treatment tank. A partition 215 extends crosswise of the lower chamber and has a port 216 therein and a passage 217 which communicates therewith and is arranged for connection to the service line. The axis of the port 216 is preferably disposed transverse to the axis of the valve body 201 and an auxiliary valve member 219 is provided for controlling the flow through the port 216. The auxiliary valve member includes a plurality of annularly spaced guide fingers 221 and a resilient valve face 222, herein shown in the form of a cup washer, which is arranged to seal against the walls of the port 216 when the valve member is closed.

The valve body 201 has a lateral extension 225 aligned with the port 216 and a sleeve 226 is disposed in the extension to form a cylinder for slidably receiving the auxiliary valve operating plunger 227. The latter is loosely disposed in the cylinder and sealed thereto as by an O-ring 228 and is connected through a stem 229 to the auxiliary valve member 219. As in the preceding embodiment, the plunger 227 has a port 231 extending therethrough. A head 233 is attached to the end of the lateral extension 225 as by fasteners 234 and is sealed thereto by a gasket 235. The head 233 overlies the end of the sleeve 226 to close the same and has a passage 237 formed therein, one end of which is connected through a conduit 238 to drain. The other end of the passage 237 communicates with a passage 239 formed in the lateral extension 225, which last-mentioned passage communicates with a passage 241 formed in the valve body 201 along the side thereof. The upper end of the passage 241 is sealed as by a removable plug 242.

An annular rib 244 is formed in the upper chamber 203 intermediate the ends thereof and extends into closely spaced adjacency to the head 208 to define a restricted flow passage therebetween and provision is made for selectively communicating the upper chamber 203 at a point above the rib 244 with the drain passage 241 under the control of the first drain valve 12b. For this purpose, a chambered boss 245 is formed on the valve body 201 adjacent the upper end thereof and at the side adjacent the drain passage 241. The chamber 246 in the boss 245 is communicated with the drain passage through a port 247 and a valve seat 248 is formed around the port. The solenoid operated valve 12b is threaded into the boss 245 and has a movable plunger 249 normally biased by a spring 251 to a position blocking fiow through the port 247. A passage 252 is formed in the valve body and boss 245 to communicate the chamber 246 'with the top chamber 203 whereby to selectively pass fluid from the top chamber to the drain passage 241 when the first drain valve 12b is opened.

A chamber 255 is formed in the head 233 and communicates through a port 256' with the drain passage 237 in the head. A valve seat 257 is provided around the port 256 and is arranged to be closed by the plunger 258 of the second drain valve 13b. The plunger 258 is normally biased by a spring 259 to a position blocking flow through the port 256. A passage 261 is formed in the head 233 and communicates the chamber 255 therein with the cylinder 226 so as to thereby selectively pass liquid from the cylinder to drain, when the second drain valve 13b is opened.

The ejector 14b is located in a boss 260' formed on the side of the valve body 201 and which extends between the lower chamber 204 and the upper chamber 203. The boss 261 as shown in FIG. 8, has a bn'ne inlet chamber 262 formed intermediate the ends thereof which communicates through a conduit 263 and brine control valve 16b with the brine tank 15b. A raw water inlet chamber 264 is formed in the lower end of the boss 261 and a nozzle 265 is inter-posed between the raw Water inlet chamber 264 and the brine inlet chamber 262. A passage 266 is formed in the boss 261 to communicate the brine inlet chamber with the top chamber 203 and a throat 267 is threaded into the passage. For reasons set forth more fully hereinafter, a ball check valve 268 is disposed in the passage 266 and cooperates with the outlet of the throat 267 to block reverse flow of liquid through the ejector. A pin 269 is mounted to extend crosswise of the passage 266 and prevent the ball check valve from passing outwardly of the passage.

During the normal service run, the valve member 207 is in the position shown in FIG. 7 and raw water flows from the inlet passage 200 through the inlet chamber 202, top port 205 and top chamber 203 to the conduit 212 leading to the top of the treatment tank 10b. The treated water flowing from the bottom of the treatment tank flows through conduit 213 and through port 216 to the service passage 217. As will be noted, the flow of water through port 216 to service will produce a pressure un balance on the auxiliary valve member 219 which urges the latter to its open position shown in FIG. 7.

In order to backwash the bed of exchange material the first drain valve 12b is opened under the control of a timer 275 to liquid from the upper chamber 203 to drain. This produces a pressure unbalance on the head 208 which raises the valve member 207 to the position shown in 'FIG. 8 blocking flow through port 205. Raw water then flows downwardly through the port 206 and through port 216 to the conduit leading to the bottom of the treatment tank, to backwash the same, the effiuent from the top of the treatment tank flowing through conduit 212, past the rib 244 and through passage 252 and port 247 to drain. In the normal backwash rates, the flow of backwash water from the port 206 through the port 216 is normally insufiicient to cause movement of the auxiliary valve member 219 to a position blocking flow through port 216. However, for high backwash rates, a spring such as 138 described in connection with the previous embodiment may be provided for yieldably maintaining the auxiliary valve in its opened position. Alternatively, a check valve herein shown in the form of a resilient flapper valve 272 may be attached to the piston 227 to overlie the port 231 therein. The flap valve 272 closes when the second drain valve 13b is closed, and, in conjunction with the piston 227, forms a dash pot which prevents movement of the auxiliary valve 219 to its closed position until the second drain valve 13b is opened. The size of the passages 252 and port 247 is regulated to provide the desired backwash rate of flow and thereby maintain the top chamber 203, and conduits 212 and 213 under a relatively high pressure. Since the inlet and outlet ends of the ejector 14b are under substantially the same pressure under these conditions, substantially no fluid flows through the ejector.

At the completion of the backwash phase of the regeneration cycle, the timer 275 opens the second drain valve 13b and closes the first drain valve 12b. The liquid at the left hand side of piston 227 then flows to drain through the passage 261 and port 256 and moves the piston 227 and valve member 219 to the lett to close the port 216. The flap valve 272 opens and permits fluid to flow past the piston 227 to drain. As described in connection with the preceding embodiment, the flow impedance of the passage 231 is made less than that of the ejector 14b so as to maintain arelatively low pressure at the outlet of the ejector. Raw water then flows from the lower chamber 204 through the ejector 14b and draws brine from the brine tank 15b to pass the same to the top of the treatment tank. The effluent from the bottom of the treatment tank, as previously described, flows through the port 231 and the piston 227 to drain. Upon completion of the brine injection phase, the brine valve 16b closes so that the water passing through the ejector is efie ctive to rinse the bed of exchange material. At the completion of the rinse phase of the regeneration cycle, the second drain valve 131) is closed and the pressure builds up in the conduit 213, tank 10b and conduit 212 until the pressure on opposite sides of the valve member 207 are equalized and the latter drops to the position shown in FIG. 7.

When the services line valve (not shown) is open to pass water from the service passage 217, the treated water impinges upon the auxiliary valve member 219 and moves the'same to its opened position. The ball valve 268 in the ejector passage drop to-a position closing the outlet of the throat 267 and prevents the flow of untreated water from the top passage through the ejector and through the bottom chamber 204 to service.

We claim:

1. A control system for a water treatment apparatus having a treatment tank with a bed of exchange material therein, said control system comprising a two position control valve including casing means defining an inlet chamber and first and second outlet chambers, said casing means having an inlet passage communicating with said inlet chamber and upper and lower valve ports respectively communicating said inlet chamber with said first and second outlet chambers, said control valve having a control valve member disposed within said inlet chamber and movable between a lower position blocking flow through said lower valve port and an upper position blocking flow through said upper valve port and adapted to be held in said upper position closing said upper valve port in response to a pressure difierential between said inlet chamber and said first outlet chamber, an upper passage means'communicating with said first outlet chamber and adapted for communication with the upper end of the treatment tank above the bed of exchange material therein, a lower passage means adapted for communication with the lower end of the treatment tank below the bed of exchange material therein, a first drain passage communicating with said upper passage means for passing fluid to drain from the upper end of said tank, a first drainvalve movable independent of said control valve member for controlling flow through said first drain passage, fluid operated means connected to said control valve r. 12 member and disposed in the path of flow of fluid to said first drain passage for moving said control Valve member to itsraised position closing said upper valve port and opening said lower valve port when said first drain valve is opened, a second drain passage communicating with said lower passage means for passing liquid to drain from the lower end of the tank, a second drain valve movable independent of said control valve member for controlling flow through said second drain passage, said lower drain valve being operative when open to pass fluid from the lower end of the treatment tank to drain, first and second operating means for respectively operating said first and second drain valves, and means for sequentially actuating said first and second operating means, said casing means defining an auxiliary valve port com- .municating said second outlet chamber and said lower flow passage, an auxiliary valve member movable independent of said control valve member into and out of position closing said auxiliary port, means for closing said auxiliary valve means when said second drain valve is open, and regenerant feed means for feeding fluid into the upper end of said treatment tank when said second drain valve is open.

2. A control system for a water treatment apparatus having a treatment tank with a bed of exchange material therein, said control system comprising a two-position control valve including casing means defining an inlet chamber and first and second outlet chambers, said casing means having an inlet passage communicating with said inlet chamber and upper and lower valve ports respectively communicating said inlet chamber with said first and second outlet chambers, said control valve having a control valve member disposed within said inlet chamber and movable between a lower position blocking flow through said lower valve port and an upper position blocking flow through said upper valve port and adapted to be held in said upper position closing said upper valve port in response to a pressure difierential' between said inlet chamber and said first outlet chamber, an upper passage means communicating with said first outlet chamber and adapted for communication with the upper end of the treatment tank above the bed of exchange material therein, a lower passage means adapted for communication with the lower end of the treatment tan-k below the bed of exchange material therein, a first drain passage communicating with said upper passage means for passing fluid to drain from the upper end of said tank, a first drain valve movable independent of said control valve member for controlling flow through said first drain passage, fluid operated means connected to said control valve member and disposed in the path of flow of fluid to said first drain passage for moving said control valve member to its raised position closing said upper valve port and opening said lower valve port when said first drain valve said first and second operating means, a regenerant feed ejector having a raw water inlet and an outlet, said casing means defining an auxiliary valve port communicating said second outlet chamber and said lower flow passage, said casing mean also defining a regenerant control port between said second outlet cham-ber and said raw water inlet of the ejector, an auxiliary valve member movable independent of said control valve member between a first:

position blocking flow through said auxiliary port and a second position blocking flow through said regenerant con trol port, and means operative when said second drain' 13 valve is opened for moving said auxiliary valve member to said first position.

3. A control system for a water treatment apparatus having a treatment tank with a bed of exchange material therein, said control system comprising a two-position control valve including casing means defining an inlet chamber and first and second outlet chambers, said casing means having an inlet passage communicating with said inlet chamber and upper and lower valve ports respectively communicating said inlet chamber with said first and second outlet chambers, said control valve having a control valve member disposed within said inlet chamber and movable between a lower position blocking flow through said lower valve port and an upper position blocking flow through said upper valve port and adapted to be held in said upper position closing said upper valve port in response to a pressure differential between said inlet chamber and said first outlet chamber, an upper passage means communicating with said first outlet chamber and adapted for communication with the upper end of the treatment tank above the bed of exchange material therein, a lower passage means adapted for communication with the lower end of the treatment tank below the bed of exchange material therein, a first drain passage communicating with said upper passage means for passing fluid to drain from the upper end of said tank, a first drain valve movable independent of said control valve member for controlling flow through said first drain passage, fluid operated means connected to said control valve member and disposed in the path of flow of fluid to said first drain passage for moving said control valve member to its raised position closing said upper valve port and opening said lower valve port when said first drain valve is opened, a second drain passage communicating with said lower passage means for passing liquid to drain from the lower end of the tank, a second drain valve movable independent of said control valve member for controlling flow through said second drain passage, said lower drain valve being operative when open to pass fluid from the lower end of the treatment tank to drain, first and second operating means for respectively operating said first and second drain valves, and means for sequentially actuating said first and second operating means, a regenerant feed ejector having a raw water inlet and an outlet, said casing means defining an auxiliary valve port between said second outlet chamber and said lower flow passage, said casing means also defining a regenerant control port communicating said second outlet chamber and said raw water inlet of the ejector, an auxiliary valve member movable independent of said control valve member between a first position blocking flow through said auxiliary port and a second position blocking [flow through said regenerant control port, fluid operated means connected to said auxiliary valve member and disposed in the path of flow of fluid to said second drain passage for moving said auxiliary valve member to said first position closing said auxiliary port when said second drain valve is open.

4. A control system for a Water treatment apparatus having a treatment tank with a bed of exchange material therein, said control system comprising a two-position control valve including casing means defining an inlet chamber and first and second outlet chambers, said casing means having an inlet passage communicating with said inlet chamber and upper and lower valve ports respectively communicating said inlet chamber with said first and second outlet chambers, said control valve having a control valve member disposed within said inlet chamber and movable between a lower position blocking flow through said lower valve port and an upper position blocking flow through said upper valve port and adapted to be held in said upper position closing said upper valve port in response to a pressure difierential between said inlet chamber and said first outlet chamber, an upper passage means communicating with said first outlet chamber and adapted for communication with the upper end of the treatment tank above the bed of exchange material therein, a lower passage means adapted for communication with the lower end of the treatment tank below the bed of exchange material therein, a first drain passage communicating with said upper passage means for passing fluid to drain from the upper end of said tank, a first drain valve controlling flow through said first drain passage operative upon opening to pass fluid from the upper end of said treatment tank to drain, means responsive to opening of said first drain valve for raising said control valve member to its upper position blocking flow through said upper valve port and opening said lower valve port, a second drain passage communicating with said lower passage means for passing liquid to drain from the lower end of the tank, a second drain valve movable independent of said control valve member for controlling flow through said second drain passage, said second drain valve being operative when open to pass fluid from the lower end of the treatment tank to drain, first and second operating means for respectively operating said first and second drain valves, and timer controlled means for sequentially actuating said first and second operating means, said casing means defining an auxiliary valve port communicating said second outlet and said lower flow passage, said casing defining an operator chamber aligned with said auxiliary port and extending between said lower flow passage and said second drain passage, an auxiliary valve member movable independent of said main valve member for closing said auxiliary valve port, a head attached to said auxiliary valve member slidably disposed in said operator chamber and defining a restricted flow passage between said lower flow passage and said second drain passage, said head being operative when said second drain valve is opened to move said auxiliary valve member to a position closing said auxiliary valve port.

5. The combination of claim 4 wherein said head has an opening extending therethrough, and a check valve in said opening operative to open and permit flow to said second drain passage.

6. A control system for a water treatment apparatus comprising first and second valve means, said first valve means including a casing defining an inlet chamber and first and second outlet chambers, first and second valve ports respectively communicating said inlet chamber with said first and second outlet chambers, a two-position control valve movable between a first position blocking flow through said second valve port and a second position blocking flow through said first valve port and opening said second port, a first flow passage communicating with said first outlet chamber and adapted for communication with one end of a treatment tank, a first drain passage communicating with said first flow passage and said first outlet chamber, a first drain valve controlling flow through said first drain passage, said second valve means including casing means defining a second flow passage adapted for communication with the other end of a treatment tank and a third valve port communicating said second outlet chamber and said second flow passage, a second valve member movable independent of said first valve member between a first position opening said third port and a second position closing said third port, a second drain passage communicating with said second flow passage for passing fluid from said other end of the tank to drain, a second drain valve controlling flow through said second drain passage, first and second operating means for opening said first and second drain valves, timer controlled means for sequentially actuating said first and second operating means, means responsive to opening of said first drain valve for moving said first valve member from said first position to said second position thereof, and means responsive to opening of said second drain valve for moving said second valve member from its first position to said second position thereof.

7. A control system for a water treatment apparatus comprising first and second valve means, said first valve means including a casing defining an inlet chamber and first and second outlet chambers, first and second valve ports respectively communicating said inlet chamber with said first and second outlet chambers, a two-position control valve movable between a first position blocking flow through said' second valve port and a second position blocking flow through said first valve port and opening said second port, a first fiow passage communicating with said first outlet chamber and adapted for communication with one end of a treatment tank, a first drain passage communicating with said first flow passage and said first outlet chamber, a first drain valve controlling flow through said first drain passage, said second valve means including casing means defining a second flow passage adapted for communication with the other end of a treatment tank and a third valve port communicating said second outlet chamber and said second flow passage, a second valve member movable independent of said first valve member between a first position opening said third port and a second position closing said third port, a second drain passage communicating with said second flow passage for passing fluid from said other end of the tank to drain, a second drain valve controlling flow through said second drain passage, first and second operating means for opening said first and second drain valves, timer controlled means for sequentially actuating said first and second operating means, fluid operated means connected to said first valve member and disposed in the path of flow to said first drain passage for moving said first valve member from said first to said second position thereof when said first drain valve is opened, and fluid operated means connected to said second valve member and disposed in the path of flow to said second drain passage for moving said second valve member from said first to said second position thereof when said second drain valve is opened.

8. A control system for a water treatment apparatus comprising first and second valve means, said first valve means including a casing defining an inlet chamber and first and second outlet chambers, first'and second valve ports respectively communicating said inlet chamber with said first and second outlet chambers, a two-position control valve movable between a first position blocking flow through said second valve port and a second position blocking fiow through said first valve port and opening said second port, a first flow passage communicating with said first outlet chamber and adapted for communication with one end of a treatment tank, a first drain passage communicating with said first flow passage and said first outlet chamber, a first drain valve controlling flow through said first drain passage, an ejector having a raw water inlet and an outlet, passage means communicating said outlet of said ejector With said first passage means, a second flow passage adapted for communication with the other end of a treatment tank, said second valve means including a third port communicating said second outlet chamber and said second flow passage and a fourth port communicating said second outlet chamber and said inlet of said ejector, said' second valve means also including a second valve member movable between a first position blocking flow through said fourth port and a second position blocking flow through said third port, a second drain passage communicating with said second flow passage for passing fluid from said other end of the tank to drain, -a second drain valve controlling flow through said second drain passage, first and second operating means for opening said first and second dr-ain valves, means for sequentially actuating said first and second operating means, means responsive to opening of said first drain valve for moving said first valve member from said first position to said second position thereof, and means responsive to opening of said second drain valve for moving said second valve member from said first to said second position thereof.

9. A control system for a water treatment apparatus comprising first and second valve means, said firstvalve means including a casing defining an inlet chamber and first and second outlet chambers, first and second valve ports respectively communicating said inlet chamber with said first and second outlet chambers, a two-position control valve movable between a first position blocking fiow through said second valve port and a second position blocking flow through said first valve port and opening said second port, a first flow passage communicating with said first outlet chamber and adapted for communication with one end of a treatment tank, a first drain passage communicating with said first flow passage and said first outlet chamber, a first drain valve controlling flow through said first drain passage, an ejector having a raw water inlet and an outlet, passage means communicating said outlet ofsaid ejector with said first flow passage, "a second flow passage adapted for communication with the other end of a treatment tank, said second valve means including a third port communicating said second outlet chamber and said second flow passage and a fourth port communicating said second outlet chamber and said inlet of said ejector, said second valve means also including a second valve member movable between a first position blocking flow through said fourth port and a second position blocking flow through said third port, a second drain passage communicating with said second flow passage for passing fluid from said other end of the tank to drain, a second drain valve controlling flow through said second drain passage, first and second operating means for opening said first and second drainvalves, means for sequentially actuating said first and second operating means, a first fluid operated means connected to said first valve member and disposed in the path of flow to said first drain passage for moving said first valve member from said first to said second position thereof when said first drain valve is opened, and a second fluid operated means connected to said second valve member and disposed in the path of flow to said second drain passage for moving said second valve member from said first to said second position thereof when said second drain valve is opened.

10. The combination of claim 9 wherein said second fluid operated means comprises a piston having an opening therethrough, and a check valve on the piston operative to open and permit flow from the second flow passage to said second drain passage.

11. A control system for a Water treatment apparatus comprising first and second valve means, said first valve means including a casing defining an inlet chamber and first and second outlet chambers, upper and lower valve ports respectively communicating said inlet chamber with said first and second outlet chambers, said control valve having a two-position control valve movable between a lower position blocking flow through said lower valve port and a raised position blocking fiow through said upper valve port and adapted to be held in said upper position closing said upper valve port in response to a pressure differential between said inlet chamber and said upper outlet chamber, a first flow passage communicating with said first outlet chamber and adapted for communication with one end of a treatment tank, a first drain passage communicating with said first flow passage and said first outlet chamber, a first drain valve controlling flow through said first drain passage, said second valve means including casing means defining a second flow passage adapted for communication with the other end of a treatment tank and a third valve port communicating said second outlet chamber and said second flow passage, a second valve member movable independent of said first valve member between a first position opening said third port and a second position closing said third port, a second drain passage communicating with said second flow passage, for passing fluid from said other end of the tank to drain, a second drain valve controlling flow through said second drain passage, first and second operating means for opening said first and second drain valves, means for sequentially actuating said operating means, means responsive to opening of said first drain valve for moving said first valve member from said lower to said raised position thereof, and means responsive to opening of said second drain valve for moving said second valve member from said first to said second position thereof.

12. The combination of claim 11 including a regenerant feed ejector having a raw water inlet and an outlet, and a third passage means communicating said inlet of said ejector with said second outlet chamber.

13. The combination of claim 12 wherein said second valve member has means thereon for blocking fiow through said third passage means when said second valve member is in said first position thereof.

14. The combination of claim 12 including a check valve in said outlet of said ejector operative to close to prevent flow in a direction from the outlet to the inlet of the ejector.

15. A control system for reversibly controlling fluid flows comprising, a two-position control valve including casing means defining an inlet chamber and first and second outlet chambers, said casing means having an inlet passage communicating with said inlet chamber and first and second valve ports respectively communicating said inlet chamber With said first and second outlet chambers, said casing means having an outlet flow passage and a third port communicating said second outlet chamber with said outlet flow passage, passage means communicating said first outlet chamber and said outlet flow passage, a first drain passage communicating with said first outlet chamber and said passage means adjacent one end of the latter for passing fluid to drain from said one end of the passage means, a first drain valve controlling flow through said first drain passage, a pressure responsive valve member controlling flow from said inlet chamber through said first and second valve ports and movable in response to opening of said first drain valve from a first position closing said second valve port toa second position closing said first valve port, said pressure responsive valve member being adapted to be held in said second position closing said first port when the pressure in said first outlet chamber is less than the pressure in said inlet chamber, a second drain passage communicating with said outlet flow passage and said passage means adjacent the other end of the latter for passing fluid to drain from said other end of said passage means, a second drain valve movable independent of said pressure responsive valve member for controlling flow through said second drain passage, said second drain valve being operative upon opening to pass fluid from said other end of said passage means to drain to thereby reduce the pressure in said first outlet chamber and hold said valve member in said second position when said first drain valve is closed, means for closing said third port when said second drain valve is open, first and second means for respectively operating said first and second drain valves, and timer controlled means for sequentially actuating said first and second operating means.

16. A control system for reversibly controlling fluid flows comprising, a two-position control valve including casing means defining an inlet chamber and first and second outlet chambers, said casing means having an inlet passage communicating with said inlet chamber and first and second valve ports respectively communicating said inlet chamber with said first and second outlet chambers, said casing means having an outlet flow passage and a third port communicating said second outlet chamber with said outlet flow passage, passage means communicating said first outlet chamber and said outlet flow passage, a first drain passage communicating with said first outlet chamber and said passage means adjacent one end of the latter for passing fluid to drain from said one end of the passage means, a first drain valve controlling flow through said first drain passage, a pressure responsive valve member controlling flow from said inlet chamber through said first and second valve ports and movable in response to opening of said first drain valve from a first position closing said second valve port to a second position closing said first valve port, said pressure responsive valve member being adapted to be held in said second position closing said first port when the pressure in said first outlet chamber is less than the pressure in said inlet chamber, a second drain passage communicating with said outlet flow passage and said passage means adjacent the other end of the latter for passing fluid to drain from said other end of said passage means, a second drain valve movable inde pendent of said pressure responsive valve member for controlling flow through said second drain passage, means communicating with said passage means for feeding a restricted flow of fluid thereto, said second drain valve being operative when open to pass fluid from said other end of the passage means to drain at a rate greater than said restricted flow to maintain the pressure in said first outlet chamber below the pressure in said inlet chamber and thereby produce a pressure unbalance on said valve member for holding the same in said second position, means for closing said third port when said second drain valve is open, first and second means for respectively operating said first and second drain valves, and timer controlled means for sequentially actuating said first and second operating means.

17. A control system for reversibly controlling fluid flows comprising, a two-position control valve including casing means defining an inlet chamber and first and second outlet chambers, said casing means having an inlet passage communicating with said inlet chamber and first and second valve ports respectively communicating said inlet chamber with said first and second outlet chambers, said casing means having an outlet flow passage and a third port communicating said second outlet chamber with said outlet flow passage, passage means communicating said first outlet chamber and said outlet flow passage, a first drain passage communicating with said first outlet chamber and said passage means adjacent one end of the latter for passing fluid to drain from said one end of the passage means, a first drain valve controlling flow through said first drain passage, a pressure responsive valve member controlling flow from said inlet chamber through said first and second valve ports and movable in response to opening of said first drain valve from a first position closing said second valve port to a second position closing said first valve port, said pressure responsive valve member being adapted to be held in said second position closing said first port when the pressure in said first outlet chamber is less than the pressure in said inlet chamber, a second drain passage communicating with said outlet flow passage and said passage means adjacent the other end of the latter for passing fluid to drain from said other end of said passage means, a second drain valve movable independent of said pressure responsive valve member for controlling flow through said second drain passage, means communicating with said passage means for feeding a restricted flow of fluid thereto, said second drain valve being operative when open to pass fluid from said other end of the passage means to drain at a rate greater than said restricted flow to maintain the pressure in said first outlet chamber below the pressure in said inlet chamber and thereby produce a pressure unbalance on said valve member for holding the same in said second position, an auxiliary valve member movable independent of said pressure operated valve member for closing said third port, auxiliary valve operating means for moving said auxiliary valve member to a closed position when sa d second drain valve is open, first and second means for respectively operating said first and second drain valves, and timer controlled means for sequentially actuating said first and second operting means.

18. The combination of claim 17 wherein each of said first and second operating means and said auxiliary valve operating means are electrically actuated.

19 The combination of claim 17 wherein said auxiliary l9 valve operating means comprises means on said auxiliary valve member operative in response to the pressure condition in said second drain passage for closing said auxiliary valve member when said second drain valve is opened.

20. A control system for reversibly controlling fluid flows comprising, a two-position control valve including casing means defining an inlet chamber and first and second outlet chambers, said casing means having an inlet passage communicating with said inlet chamber and first and second valve ports respectively communicating said inlet chamber with said first and second outlet chambers, said casing means having an outlet flow passage and a third port communicating said second outlet chamber with said outlet flow passage, passage means communicating said first outlet chamber and said outlet flow passage, a first drain passage communicating with said first outlet chamber and said passage means adjacent one end of the latter for passing fluid to drain from said one end of the passage means, a first drain valve controlling flow through said first drain passage, a pressure responsive valve member controlling flow from said inlet chamber through said first and second valve ports and movable in response to opening of said firstdrain valve from a first position closing said second valve port to a second position closing said first valve port, said pressure responsive valve member being adapted to be held in said second position closing said first port when the pressure in said first outlet chamber is less than the pressure in said inlet chamber, a second drain passage communicating with said outlet flow passage and said passage means adjacent the other end of the latter for passing fluid to drain from said other end of said passage means, a second drain valve movable independent of said pressure responsive valve member for controlling flow through said second drain passage, said second drain valve beig operative upon opening to pass fluid from said other end of said passage means to drain to thereby reduce the pressure in said first outlet chamber and hold said valve member in said second position when said first drain valve is closed, auxiliary valve means movable independent of said valve member and operative in response to opening of said second drain valve for closing said third port, and means for sequentially operating said first and second drain valves.

21. A control system for reversibly controlling fluid flows comprising, a two-position control valve including casing means defining an inlet chamber and first and second outlet chambers, said casing means having an inlet passage communicating with said inlet chamber and first and second valve ports respectively communicating said inlet chamber with said first and second outlet chambers, said casing means having an outlet flow passage and a third port communicating said second outlet chamber with said outlet flow passage, passage means communicating said first outlet chamber and said outlet flow passage, a first drain passage communicating With said first outlet chamber and said passage means adjacent one end of the latter for passing fluid to drain from said one end of the passage means, a first drain valve controlling flow through said first drain passage, a pressure responsive valve member controlling flow from said inlet chamber through said first and second valve ports and movable in response to opening of said first drain valve from a first position closing said second valve port to a second position closing said first valve port, said pressure responsive valve member being adapted to be held in said second position closing said first port when the pressure in said first outlet chamber is less than the pressure in said inlet chamber, a second drain passage communicating with said outlet flow passage and said passage means adjacent the other end of the latter for passing fluid to drain from said other end of said passage means, a second drain valve movable independent of said pressure responsive valve member for controlling flow through said second drain passage, an ejector having an outlet communicating With said passage means and an inlet communicating with said second outlet chamber for feeding a restricted flow of fluid to said passage means, said second drain valve being operative when open to pass fluid from said other end of said passage means to drain at a rate greater than the flow from said ejector to said passage means to maintain the pressure in said first outlet chamber substantially below the pr ssure in said inlet chamber, an auxiliary vaive movable independent of said pressure operated valve member from a first position blocking flow to said inlet of the ejector to a second position blocking flow through said third port, means responsive to opening of said second drain valve for moving said auxiliary valve member from said first to said second position, and means for sequentially opening said first and second drain valves.

References Cited in the file of this patent UNITED STATES PATENTS Clark Dec. 9, 1941 

